Wheel-assembly monitor for diagnosing passing railroad trains

ABSTRACT

A monitor to diagnose wheel assemblies of passing railroad trains, the monitor being characterized in that a cavity is present in and parallel to a measurement tie or in a hollow railroad tie, the cavity housing infrared deflection units and at least one infrared detector which make it possible to monitor all heat sources present in the vicinity of the wheel assembly and the undercarriage of the train car while offering maximum protection against mechanical and electrical factors. The wheel pressure and accelerator pickups introduced with the monitor allow accurate determination of the values needed to normalize the infrared test results such as wheel position, wheel weight and tread conditions.

BACKGROUND OF THE INVENTION

a) Field of the Invention

The invention concerns a wheel-assembly monitor to diagnose passingtrain-cars for the purpose of detecting the temperature of thewheel-assembly axles, drive, braking and bearing components, and ofother heat sources to be monitored on train-cars, in particularradiation sources supplied with heat by conduction from moving partswhich are only indirectly accessible, or whereby the temperatures ofthese components can be inferred.

b) Description of Related Art

Infrared detection systems are used in railroad systems for monitoringheat sources. These systems are affixed to concrete foundations or tothe railroad ties or rails and, in order to retain enough trainclearance, they must be mounted outside the space subtended between thetwo rails; the track being formed by two rails supported by cross-ties.

The known detection systems, however, suffer from substantial drawbacksregarding the required number of track switches, the mandatorymountings, the susceptibility of mechanical and electrical influences,the constancy of detection configuration, the detectable wheel-assemblyor components for one system per axle, and the electrical safetyconsideration of possible contact between the life-endangering voltagesand the housings of the monitors.

Detection geometries subtending slopes >90° must be used with theconventional monitors mounted between the wheels of one assembly. Thisrequires at least one additional track switch to define the measurementrange. Moreover, the fixed measurement ranges can be only covered if,for instance, electromagnetic or eddy rail-brakes are in a positionother than lowered, i.e. not in a braking position. Additionally, whenthe sun is low, its light may fall onto the system; triggering falsealarms during train travel.

The mounting of the monitor weighing up to 50 kg to the rail, tie orconcrete foundation is exceedingly laborious. The systems mounted to therails or ties are susceptible to frequent mechanical disturbances andaccordingly operation is reduced while maintenance is increased.

In such systems incurring vibrations or mechanical impacts for instancefrom parts loaded on and/or overhanging the cars, the measurementgeometry of the monitor may be imperceptibly degraded and operationalreliability may also be jeopardized. Therefore, plate guards must beinstalled to protect the monitors, as a result of which maintenance issubstantially increase. In order to allow cable exchange even in timesof frost, the cables are usually mounted off ground and on thesuperstructure. Hence such electrical connections are also frequentlydamaged.

Electrical safety against excessive high voltages (to the touch)heretofore could only be assured for the 220-volt rail-affixed monitorsand for track layouts fitted with all-clear displays by using a detectorconnected to the particular rail. If ground is lost and the infrareddetector housing is at voltage, the maintenance personnel is in lethaldanger.

SUMMARY OF THE INVENTION

The object of the invention is to overcome these drawbacks and to createa monitor scanning an arbitrary component of a wheel-assembly and/ortrain car across the shortest possible measurement range. Themeasurement systems of the monitor is affixable anywhere parallel to therailroad tie, that is, also between the rails, and evinces invariantmeasurement geometries and further is insensitive both to electrical andmechanical factors.

The monitor of the invention is characterized in that the individualsources of infrared radiation of each train car and/or wheel-assemblyare scanned several times in parallel by means of appropriately mounteddeflection units, and in that the infrared radiation as a whole iscollimated onto one or more infrared detectors.

The monitor may be housed in a measurement tie mounted parallel to therailroad ties or in a hollow railroad tie.

The individual deflection units are equipped with one or more sealingunits through which the infrared radiation passes into the deflectionunit. The deflection unit can deflect the infrared radiation and/orsample it and/or optically stop it up or down.

The infrared detector is also mounted in the measurement tie or in thehollow railroad tie and is able to receive and combine several signals.On account of the comparatively large spacing from the rails and becauseof the electrical shielding by a supporting metal bar, this detector isprotected maximally against electromagnetic factors.

All supply and data lines are electrically and mechanically protected bythe metal bar.

Because the systems is affixed to the rail in the vicinity of the tieand serves to sense the wheel compression and the acceleration of therail or tie perpendicularly to the longitudinal rail axis, the wheelposition can be determined accurately. Hence, the measurement range fromaxle to axle parallel to the track axis can be ascertained and adjusted,and the test results if called for can be post-corrected in a subsequentanalyzer.

Accordingly, the temperatures of all components of wheel-assemblies andof various train cars, the total weight of the wheel-assembly, and thewheel loads are available at the analyzer.

In relation to the acceleration and wheel load values, test results arethen available which shed light on the wheel conditions such asimbalances and tread damages which cause bearing damage.

Other features and advantages of the present invention will becomeapparent from the following description of the preferred embodiment,taken in conjunction with accompanying drawings, which illustrate, byway of example, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically and in perspective shows a hollow railroad tiebetween and parallel to two conventional railroad ties;

FIG. 2 is a perspective view of the construction of the monitor in ahollow tie and the wheel assembly including drive motor, inside andoutside wheel assembly bearings, and brakes;

FIG. 3 is a vertical cross-section of the wheel assembly through thehollow tie, and schematically shows the infrared path from source todetector.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The following description of the present invention is not to be taken ina limiting sense, but is made merely for the purpose of illustrating thegeneral principles of the invention. The following description presentsthe best contemplated mode of carrying out the invention.

FIG. 1 shows a hollow railroad tie 11 between two regular ties 2 andhousing both the deflection units 9 and the infrared detector 15. FIG. 1also shows the sealing units 9a covering the deflection units and whichmay serve to eliminate outside interference with the measurement values.The sealing units are preferably electrically driven, movable, sealingunits mounted directly on the deflection units 9.

The deflection units 9 are formed in collimated manner and serve toreceive the infrared radiation generated by the components of thewheel-assembly. It should be noted that deflection units 9 haveappropriate dimensions to ensure that the detection of all components ofthe wheel-assembly can be implemented using an infrared-optical system.The deflector units 9 collimate the radiation signal and deflect thesame to the infrared detector 15.

FIG. 2 shows a wheel-assembly riding on the rails 1 resting on the ties2 and consisting of wheels 4, the wheel axle 6 and the wheel-assemblybearings 5. The axle 6 furthermore supports the drive motor 3.

Acceleration sensors 7 are mounted on the two rails 1 and are connectedthrough their terminals 7a to the analyzer 20. The acceleration sensors7 detect the wheel compression and the acceleration of the rail or tieperpendicular to the longitudinal rail axis. Therefore, the wheelposition can be determined accurately, and the measurement range fromaxle to axle parallel to the track longitudinal axis can be ascertainedand adjusted. These measurement values can be sent to the analyzer 20for post correction of the test results.

Cables 10 connecting the detector to the analyzer 20 exit from the endface of the hollow tie 11 as shown in FIG. 2.

The path of the various test rays (i.e. the measurement geometry) isshown by the arrows 8 of FIG. 3. The arrows 8 represent the infraredradiation from the various components of the drive assembly, forexample, the drive motor 3, the wheels 4, the wheel-assembly bearings 5.Additionally, FIG. 3 shows all the components of the conventionalbraking systems such as shoe, shaft-disk and wheel-disk brakes, whichare denoted by reference numeral 12. Arrows again denoted by 8 andrepresenting the infrared radiation issue from these heat generatingcomponents through the deflection units 9 to the infrared detector 15.

The detector 15 transduces the infrared into an electric output whichfurthermore is amplified. The electrical output is transmitted viacables 10 to the analyzer 20 which may be a computer processing unit foranalyzing and storing test results.

It should be noted that the path of the various test rays (i.e. themeasurement geometry) as shown by the arrows 8 of FIGS. 2 and 3, aredetermined by the arrangement of the deflection units. With reference toFIG. 2, four deflection units 9 are positioned between the rails 1,while FIG. 3 illustrates an arrangement wherein five deflection units 9are positioned to receive infrared radiation between the rails 1.

The infrared detector 15 is positioned within the measurement tie 11 tocollect the radiation data passing into and from the deflection units 9,wherein the radiation data may be collected and/or combined, thentransposed into an electric output before being sent to the analyzer 20.

From the foregoing, it is understood that the temperatures of all heatgenerating components of the wheel assemblies and of various train cars,the total weight of the wheel assembly, and the wheel loads areavailable at the analyzer or CPU 20. In relation to the acceleration andwheel load values, test results are then available which indicate wheelconditions such as imbalances and tread damages which cause bearingdamage.

While the invention has been particularly shown and described withreference to a preferred embodiment, it will be understood by thosehaving ordinary skill in the art that various changes in form and detailmay be made therein without departing from the spirit and scope of theinvention.

I claim:
 1. A monitoring and measurement system for detecting operational characteristics of a wheel/axle assembly mounted on a railed vehicle, said system comprising:a tie member supporting a pair of substantially parallel rails upon which a railed vehicle translates; at least one infrared deflection unit mounted in a collimated manner, and adapted to receive and collimate infrared radiation from said wheel/axle assembly; an infrared detection means for receiving collimated infrared radiation from said at least one deflection unit, said infrared detection means being positioned between said parallel rails, wherein said collimated infrared radiation is transduced into electrical signals representing the wheel/axle assembly's temperature and operational characteristics, wherein said deflection unit is mounted in said tie member.
 2. The monitoring and measurement system of claim 1, further comprising at least one position sensing means mounted on said rail for generating a position signal representing a position of said wheel/axle assembly, said position signal being interfaced with said electrical signal to further detect the operational characteristics of said wheel/axle assembly.
 3. The monitoring and measurement system of claim 1, further comprising an acceleration sensor mounted on said rail for detecting an acceleration of said wheel/axle assembly and generating an acceleration signal.
 4. The monitoring and measurement system of claim 3, further comprising an analyzer means for receiving said electrical signal and said acceleration signal, whereby said analyzer analyzes said electrical signal and said acceleration signal to determine the wheel/axle assembly's operational characteristics.
 5. The monitoring and measurement system of claim 4, wherein said at least one infrared deflection unit, said detection means, and said analyzer are rigidly mounted in said tie member.
 6. The monitoring and measurement system of claim 4, wherein said at least one infrared deflection unit, said detection means, and said analyzer are mounted in said tie member so as to be damped against vibration.
 7. The monitoring and measurement system of claim 1, further comprising a sensor means mounted on said rail for detecting said wheel/axle assembly's weight, and generating a weight signal.
 8. The monitoring and measurement system of claim 7, further comprising an analyzer means for receiving said electrical signal and said weight signal, whereby said analyzer analyzes said electrical signal and said weight signals to determine the wheel/axle assembly's operational characteristics.
 9. The monitoring and measurement system of claim 1, wherein a dimension of said tie member in a longitudinal direction of said rail is such that all components of said wheel/axle assembly can be monitored using an infrared-optical system.
 10. The monitoring and measurement system of claim 1, wherein said infrared detection means is mounted in said tie member.
 11. The monitoring and measurement system of claim 1, wherein said at least one infrared deflection unit receives a train-car infrared radiation signal, said train-car being mounted on said wheel/axle assembly.
 12. The monitoring and measurement system of claim 1, wherein said at least one infrared deflection unit comprises an electrically driven, movable, sealing unit for selectively permitting infrared radiation to enter said at least one infrared deflection unit.
 13. The monitoring and measurement system of claim 1, wherein said tie member comprises dimensions similar to a standard tie for railed vehicles, and is installed transversely to a longitudinal direction of said rail.
 14. A monitoring and measurement system for detecting operational characteristics of a wheel/axle assembly mounted on a railed vehicle, said system comprising:a tie member supporting a pair of substantially parallel rails upon which a railed vehicle translates, said tie member being at least partially hollow and extending in a longitudinal direction; at least one infrared deflection unit mounted in said tie member, and adapted to receive and collimate infrared radiation from said wheel/axle assembly; an infrared detection means mounted in said tie member for receiving collimated infrared radiation from said at least one deflection unit, wherein said collimated infrared radiation passes from said at least one infrared deflection unit to said detection means within said hollow tie member.
 15. The monitoring and measurement system of claim 14, wherein said at least one infrared deflection unit receives said infrared radiation at positions both outside and between said pair of rails with respect to said longitudinal direction.
 16. The monitoring and measurement system of claim 14, wherein said at least one infrared deflection unit is positioned between said pair of rails with respect to said longitudinal direction.
 17. The monitoring and measurement system of claim 14, wherein said infrared detection means is mounted between said pair of rails.
 18. The monitoring and measurement system of claim 14, wherein said at least one deflection unit receives said infrared radiation from below said wheel/axle assembly with respect to a direction of gravity.
 19. A monitoring and measurement system for detecting operational characteristics of a wheel/axle assembly mounted on a railed vehicle, said system comprising:a tie member supporting a pair of substantially parallel rails upon which a railed vehicle translates; at least one infrared deflection unit mounted in a collimated manner, and adapted to receive and collimate infrared radiation from said wheel/axle assembly, said at least one infrared deflection unit being positioned between said parallel rails; an infrared detection means for receiving collimated infrared radiation from said at least one deflection unit, wherein said collimated infrared radiation is transduced into electrical signals representing an operational characteristic of the wheel/axle assembly; and at least one additional infrared deflection unit mounted outside said pair of rails, said at least one additional infrared deflection unit adapted to receive and collimate infrared radiation from said wheel/axle assembly and deflect the infrared radiation to said detection means. 